【Reason for Discount】Unused Amakusa Whetstone? Rotary Whetstone Round Whetstone Diameter 20cm Crack Present 4.8kg

This is a round natural whetstone.
When I received it, I was told it was Amakusa whetstone, but I cannot confirm this, so the details are unknown.
Please judge from the photos.

It has a hole in the center, and its shape suggests it may have been a grinding wheel used with machinery, but its purpose and details are unknown.

Would this be suitable for those looking for a whetstone for sharpening or polishing blades?

[Size]
Diameter: Approx. 20cm
Thickness: Just under 7cm
Center hole diameter: Approx. 1.5cm
Weight: Approx. 4.8kg

*Please allow for slight variations.
*Please also check the ruler in the photos.

[Condition]
Unused, long-term storage item.

There are stains, discoloration, chips, and minor scratches due to long-term storage.
Also, as shown in the photos, there are cracks.

Due to the cracks, it may break during transport or use.
When shipping, it will be wrapped in bubble wrap and packed with cushioning material (paper) around it.
Please only purchase if you understand that this is a reason for discount item.

Please consider it with the understanding that it may require maintenance such as flattening before use.

*Please check the condition in the photos.
*Please refrain from price negotiations.